30 amp cord??

[maxx1963]

I have a 15,000 air conditioner and a 50 amp cord on my trailer. I hate toting around that heavy 50amp cord. Can i make a 30 amp with a twistlock that fits my trailer and be ok to use the a/c on the 30 amp?

[Bean]

If you are not running too many other things...AND the cord is connected to a 30 amp breaker (not a 50 amp)...I'd say you will be alright.

But connecting a 30 amp cord to a 50 amp breaker is just asking for trouble.

P.S. It might not work anyway. I think a 50 amp cord actually has two separate 25 amp feeds. Where a 30 amp cord just has one 30 amp feed.

Bean

[maxx1963]

I have heard that you can just tie those to 25 amp terminals to the single power wire coming in from the 30. the thing is, if i have to use my 50 amp cord then i have a 30 amp cord for a extention right now, what is the difference??

[Quad]

No, a 4 prong 50 amp plug has two 120 volt 50 amp wires. So a combined total of 100 amps. That's why they have a double 50 amp breaker. You should be ok running the camper on a 30 amp cord so long as you don't run any other amp hogging items. Just remember both circuits in your camper will now be on 30 amps instead of 100 amps total.

[allmi01]

Quad, a correct here. A 50 amp cordset has 2 50 amp circuits however, the total amperage you can draw is 50 amps. 50 amps on each leg as 120 volts or 50 amps as 240 acroos both together. Since nothing the in the RV is 240 volts, you get 50 amps to play with accross 2 seperate circuits. But that is not really 100 amps.

If you do not have 2 A/C units, then you might be OK with a 30 amp cordset (and yes they are commercially available but not cheap) as long as you don't try to draw more than 30 amps total. The plugs on 30 amp and 50 amp are different as the 30 amp ony carries 1 circuit and the 50 amp carries 2 circuits.

I hope this helps some. Not trying to be critical but.. this is important as overloading electrical cords will cause fires.

Mike

[byrdr1]

Marinco 124ARV-25 RV Electrical Power Cordset (50-amp 125/250-Volt Receptacle with 30-Amp 125-Volt RV Straight Blade Plug, 25-Feet) its on Amazon.
This is what I use at home. I had the 30amp box already wired up from the popup and TT days.
So i found this cord set and it keeps my heavy 50 amp cord in the camper safe and sound. I run the 15K main AC but have never run both. I dont use anything other than the frig as cold place for can goods.
randy

[maxx1963]

I was going to use the 50 amp twistlock plug with the 30 amp on the other end. I have 8/4 and 10/4 wire at home to make my own length. i was thinking like 50 or 60 ft to minimize extention cords.

my 8/4 wire says it is good for 55amps, so I should be safe with that even if i get to a 50amp service campground.

all 4 wires will go on the twistlock and at the 30amp end, the 2 hot wires will join into one, correct?

[byrdr1]

Originally Posted by maxx1963

I was going to use the 50 amp twistlock plug with the 30 amp on the other end. I have 8/4 and 10/4 wire at home to make my own length. i was thinking like 50 or 60 ft to minimize extension cords.

my 8/4 wire says it is good for 55amps, so I should be safe with that even if i get to a 50amp service campground.

all 4 wires will go on the twistlock and at the 30amp end, the 2 hot wires will join into one, correct?

8/4 for the 50 ft Plus length.
10/3 for 30ft or less. my opinion only..
randy

[Bob Landry]

There is a considerable amount of misinformation here pertaining to 50A service. 50A service consists of two 115V, 50A sources, 180 degrees out of phase and referenced to a common neutral. It will feed two sets of circuit breakers with 115V and 50A per side, so there is actually 100A available at the panel on each leg. You are not splitting 50A between two legs, you are splitting 100A between two legs because each leg has 50A available.

My concern with what the OP wants to do is that he will still be plugging into a 50A inlet at the trailer. If he plugs into a 30A outlet at the pedestal, it can work, but if he is intending to plug into a 50A outlet and use only one leg, he still has a trailer with a power leg that can accept 50A service, a power source that can provide it, joined with a 30A(10g a) cable connecting them. Unless he has a way to monitor and insure that he is only drawing 30A max, that's potentially a fire waiting to happen.

I've been in the marine service business for 15 years and I've seen firsthand the problems introduced by owners wanting to modify existing electrical systems, so my advice is that unless he is versed in 30A/50A service, he would do well to pick up a Marinco catalogue and start looking for a commercially made adapter for both ends of that 30A power cord.

Truthfully, how much hassle can it be to use a power cord that is designed to provide all of the power you would need in a travel trailer?

[Bob Landry]

Originally Posted by maxx1963

I was going to use the 50 amp twistlock plug with the 30 amp on the other end. I have 8/4 and 10/4 wire at home to make my own length. i was thinking like 50 or 60 ft to minimize extention cords.

my 8/4 wire says it is good for 55amps, so I should be safe with that even if i get to a 50amp service campground.

all 4 wires will go on the twistlock and at the 30amp end, the 2 hot wires will join into one, correct?

Your 8/4 wire is labeled incorrectly or it is refering to DC. #6 is only rated for 50A. #8 is smaller and is capable of carrying less current. If you are going to have a 50-60' run. you really need to increase a size. That would put you at 8Ga, so at that point, a 50A cable isn't that much heavier and you are assured of having all of the power you might need.

[maxx1963]

I have the wire and the twist lock plug, all I would heve to buy is the 30amp plug, so I was trying to save some money and make my own length.

I see all the adapters they make and it can not be complex. And how can they go from a 50amp twist lock to a regular 110v plug?

I can buy the cord I want to make, I was just trying to save money, and I have never been to a campground that has 50amp service.